I've been riding my GT just in an urban setting (750+mi) using the following tether that I got off Amazon. Very comfortable. Since I'm a regular rider, I attach it to my toe-side aft rail and my right forearm. It might work as a trail accessory also. In a previous thread we discussed some +/-'s.

Abahub Premium Coil SUP Leash, 10... https://www.amazon.com/dp/B072Z9CGRK?ref=ppx_pop_mob_ap_share